Batteries used in the generation of electrical energy can take on various forms. Two of the most common forms of batteries in use today are the dry cell battery and the lead-acid storage battery. Dry cell batteries were named because the electrolyte is typically comprised of a non-spillable paste-like substance. Dry cell batteries find widespread usage in such items as flashlights, portable radios, hearing aids, and other electrical devices which are frequently carried about by a user. Lead-acid storage batteries are comprised of a lead dioxide, lead plates, and aqueous sulfuric acid all disposed within a sealed container.
Batteries age over time with use and thus have limited life times. In the case of rechargeable batteries, a charger is frequently connected to the battery to maintain the battery in a fully charged state. The battery may also undergo frequent testing to determine its condition and provide an indication of expected continued operation. Current battery test procedures require disconnection or removal of the battery from its operating circuit. This type of testing not only typically requires human intervention, but also frequently results in system downtime. Disconnection of the battery from its associated load may require an alternative power source for temporary use or a separate backup power system, both of which increase the cost for ensuring reliable battery powered operation. In addition, while current battery testers are capable of providing an indication of current battery status, they do not provide an indication of possible imminent battery failure such as due to sulfation.
The present invention addresses the aforementioned limitations of the prior art by providing a live circuit battery testing arrangement to allow for the manual or automatic testing of batteries under computer control while the batteries are under load without disconnection from or interruptions in the operation of the system. The battery and its associated charger are not disconnected from the load during the battery test procedure and an indication is provided if the tester has failed and/or the charging system is inoperative. Battery testing is prevented when the batteries are being used in an emergency operation or if the batteries are being recharged following a recent discharge. The battery tester of the present invention also tests for and provides an indication of possible future battery failure such as due to sulfation.